Method of plasticizing knitted goods made from thermoplastic yarn



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. IB'IBOD'OF PLASTICIZING KNITTED GOODS [ADE FROM THERIOPLASTIC YARN 2Sheets-Sheet 1 Filed July 31, 1944 n" ET nu mmu" 0 ac w 4 Mv uwo L0H A&N

. E. COLLIDGE El AL 2,474,093

F PLASTICIZING KNITTED GOODS AD FROM THERMOPLASTIC YARN L'IET June 21,1949.

2 Sheets-Sheet 2 Filed July 31, 1944 v APmVAV$WrQVWEW 4 wmhrwavw 4 dbumab mav wgbfi ALBERT E. Cou.

IDGE,

Enwm C. DAWES 3 THOMAS A. l

. C LBERT m rams Afltfga-a M (2% Patented June 21, 1949 UNITED STATESPATENT OFFICE METHOD OF PLASTICIZING KNITTED GOODS MADE FROMTHERMOPLASTIC YARN company Application July 31, 1944, Serial No. 547,408In Great Britain May 2, 1944 4 Claims.

This invention consists in improvements in or relating to themanufacture of knitted goods and provides a new process for thetreatment of such goods made from plasticizable materials.

Hitherto, superheated and/or pressure steam has been employed for thestep of plasticizing, and the step of finishing or shaping the goods hasbeen carried out in a separate operation.

By means of the present invention the plasticizing of the knitted goodsis improved and the cost of such treatment reduced, and furthermore, ifdesired, shaping, finishing and plasticizing can be carried out in thesame operation, and plasticizing by this invention can be carried outeither prior to or after the goods have been dyed.

Finishing or shaping involves the employment of formers by which thegoods are shaped under a heat treatment and during which any creases orwrinkles in the goods are removed. This step is necessary in thefinishing of all knitted goods but in the case of articles knitted fromfilaments of plasticizable material, such as filaments of celluloseacetate composition or of vinyl cellulose composition, includingfilaments of material known as nylon, the step of plasticizing is alsorequired in order that the shape and appearance of the articles will notbe impaired when subsequently, under conditions of ordinary use they aresubjected to heat, as for instance, when they are washed. Owing to thethermoplastic nature of such materials after they are shaped andplasticized at a certain temperature they will not alter their shape andappearance when subsequently treated at a temperature somewhat less thanthat at which they are plasticized, and the plasticizing temperaturetherefore involves a temperature above boiling point of water.

According to the present invention a method of plasticizing knittedarticles of this character consists in passing the articles over and onto formers each of which provides a continuous surface possessingblack-body characteristics to underlie the article to be shaped, andsubjecting the goods on their black-body formers to externally appliedradiant heat.

Preferably the radiant heat is derived from a source producing infra-redrays.

The essential of the present invention is the employment of formershaving black-body characteristics because by their use heat from theradiating source is first absorbed by them and is then given out to thearticle stretched over it so that the latter is heated mainly by heattravelling outwardly from the inner surface of the article. This effectsa more .eflicient method of drying the articles especially of dryingthem thoroughly during shaping, finishing or drying process carried out,if desired, simultaneously with plasticizing. As a result of the presentinvention the goods obtain an improved bloom and general appearance ascompared with that of similar goods dried by known processes.

In order that the invention may be more clearly understood, preferredexamples will now be described with the aid of the accompanyingdrawings, in which Figure 1 is a plan view of apparatus embodying thefeatures of the present invention;

Figure 2 is an elevation of the apparatus shown in Figure 1, and

Figure 3 is a modification of the apparatus intended for the processingof materials to be treated.

Like reference numerals indicate like parts in the several figures ofthe drawings.

Referring first of all to Figures 1 and 2, the, knitted goods which areto be finished, and which are illustrated as hose, are trimmed andplaced on formers as at H). These formers each provide a continuoussurface possessing black-body characteristics and shaped to correspondwith and to underlie the entire inner surface of the goods to be treatedand shaped. For example, the formers may be made of aluminium colouredblack by anodizing or they may be of any other preferred materialcoloured in any known or preferred manner to afford the desired blackbody characteristics.

The articles on their formers are then placed on and carried by atravelling band composed of links H pivotally interconnected as at l2each to an adjacent link so as to form an endless band. This band iscarried over hexagonal or other preferred rollers l3 and one lap of theband travels between two banks H of infra-red lamps disposed on oppositesides of a portion of that lap of the band.

Instead of providing infra-red lamps on both sides of the band a bank ofsuch lamps may be provided on one side and instead of the lamps onlyreflectors need be employed on the other side so that the illustrationmay be taken to indicate, on one side of the band, reflectors onlywithout lamps.

Water and/or steam can be employed to increase the humidity and to addto the temperature of the articles being heated, the steam beingreleased into the air surrounding the articles which need notnecessarily be enclosed. The

sure. Alternatively, shields l of suitable material may be arranged oneach side of the articles to be treated, the material of the shieldsbeing such as to permit without hindrance passage of the requisite heatrays from the lamps and/or reflectors to the articles to be treated.These shields may be placed on both sides in the region of the banks oflamps and/or reflectors, so as to enclose a space in which humidity canbe concentrated to the required degree.

The material used for the shields w1ll be preferably, although notnecessarily, a transparent plastic, and in order that, the shape ofknitted articles shall be retained permanently it is found desirable toraise the temperature to a degree somewhat above that to whichthearticles are ever likely to be subjected in use, as, for instance,during washing.

An alternative form of apparatus is illustrated in Figure 3 which againis a plan view. This apparatus comprises two reciprocating carriers l6and I! on which the articles 10, on formers or otherwise, are carried,the example illustrated being intended to represent hose carried onformers as illustrated in Figure 1. As before, banks of infra-red lampsl4 are provided on opposite sides of the reciprocating plates at oneend, or these banks may be replaced by a single bank on one side andreflectors on the other and shields such as 15 may be employed ifdesired. Means, not shown, is provided for reciprocating thecarriers l6and I1 and the reciprocation will occur comparatively slowly so as toleave sufiicient time for those articles lying within the zone of thesource of heat to receive sufficient treatment. The articles on carrierl6 are shown in the loading and unloading position and it will beunderstood that after similar articles on carrier 11 have beensufiiciently treated they will be removed to the loading and unloadingposition and carrier 16 will simultaneously be moved to convey its loadinto the zone of heat.

We claim:

1. A process for plasticizing knitted articles 4 made from thermoplasticyarns which process consists in passing the articles over and on toformers ,each of which provides a continuous black body surface tounderlie the article to be formers to externally applied radiant heat.

3. A process for plasticizing knitted articles according to claim 1 inwhich radiant heat is applied simultaneously to the articles on theirformers from both sides of the latter.

4. A process for plasticizing knitted articles made from thermoplasticyarns which consists in passing the articles over and onto formers, eachof which provides a continuous black-body surface to underlie thearticles to be plasticized on the formers, and subjecting the articleson their black-body formers to externally applied infra-red raysdirected onto the formers whereby the latter absorb and re-radiate heatderived from the source of infra-red rays.

ALBERT EDWARD COLLIDGE. EDWIN CHARLES DAWES. THOMAS ARCHIBALD GILBERT.

REFERENCES CITED The following referenlces are of record in the file ofthis patent:

UNITED STATES PATENTS

